-LRB- CNN -RRB- -- She calls herself `` Diana , the Hunter . '' Authorities say the elusive woman has killed at least two bus drivers in Ciudad Juarez , Mexico .

According to the Chihuahua state attorney 's office , the unidentified woman , with either hair dyed blond or wearing a blond wig , shot and killed a city bus driver identified as Jose Roberto Flores Carrera , 45 , on August 28 .

Another bus driver , Fredy Zarate Morales , 32 , was killed the next day . In both cases , officials say , `` Diana , the Hunter '' boarded the buses and shot the drivers point blank .

After the second shooting , several media outlets in Ciudad Juarez reported receiving an e-mail from a sender claiming to be the killer . In the e-mail , she calls herself `` Diana , the hunter of drivers . ''

She reportedly says in the e-mails that her motive is retaliation against bus drivers who have raped vulnerable women , especially those who work in the `` maquiladoras , '' or foreign assembly plants -LRB- mainly American -RRB- on the Mexican side of the border .

`` I 'm an instrument that will avenge -LSB- the attacks against -RSB- several women , '' the e-mail is reported to say . `` We seem weak to society , but we 're truly not . We 're courageous and , if they do n't show respect to us , we will make them respect us by our own means . We women of Juarez are strong . ''

Arturo Sandoval , a spokesman with the Chihuahua state attorney 's office , told CNN the end does n't justify the means .

`` Nobody can take justice into their own hands , '' Sandoval said . `` If she was a victim of a bus driver or knows someone in that situation , she has to report it and let authorities do their job . ''

The Chihuahua state attorney 's office released a sketch of the suspect Wednesday and asked for the public 's help to catch her .

`` The sketch was done after interviewing more than 20 people who witnessed the homicides and who gave us very valuable information for this investigation , '' authorities said in a statement .

According to local media reports , citing official sources , authorities know the perpetrator is a woman because she yelled at the second victim before shooting him : `` You guys think you 're real bad , do n't you ? ''

The slayings have terrorized many bus drivers , especially those operating Route 4 , also known as the Yellow Route , which serves main thoroughfares and downtown Ciudad Juarez , a city of 1.5 million located across the border from El Paso , Texas .

Thirty drivers normally cover the route , but many have decided not to show up for work since the second slaying . Julian Vazquez , a bus driver on the same route , is one of those still behind the wheel , although he admits he 's afraid .

`` There 's only about 50 % of us working , '' Vazquez told CNN . `` We 're full of fear after learning this person killed two of our colleagues and nobody has any clue . ''

This situation has left hundreds of riders stranded . Others have been forced to look for transportation alternatives for their daily commute .

`` Of course we 're afraid , '' commuter Maria Banuelos , said . `` We fear that the driver might be attacked or that I will be in harm 's way , but we still have to get to our destination . ''

Ciudad Juarez gained international notoriety in the late 1990s and early 2000s after a wave of slayings involving women . The victims , mainly young , single women , would disappear , their bodies later found in shallow graves in desert areas around the arid city . According to an Amnesty International report , 370 young women and girl were killed in Ciudad Juarez between 1993 and 2005 . Most of the slayings remain unsolved .

Mexicans are very familiar with La Diana Cazadora , as it 's known in Spanish . A stone monument of the Roman goddess , nude , long-haired and holding a bow , stands on Mexico City 's Reforma Avenue , a major thoroughfare . A replica was erected in Ciudad Juarez .

Journalist Edgar Roman in Ciudad Juarez contributed to this report .

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Two Ciudad Juarez bus drivers were slain last month by an unidentified woman

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Shooter reportedly sent e-mails saying the killings were to avenge women raped by drivers

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Some drivers , fearful of being shot , have not shown up for work

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Commuter : `` Of course we 're afraid . ... but we still have to get to our destination . ''